A stroboscope is a device for analyzing fast motions; because of the latency properties in the human retina, a moving object seen through a rapidly switching shutter is perceived as a series of static images along the object's trajectory. In photography, a stroboscope effect can be achieved by repeatedly exposing the same film by means of a periodically switching shutter, to obtain, in the final image, repeated copies of the object along its trajectory. The same effects are achieved if, in lieu of a repeatedly switching shutter, a repeatedly switching illumination source is used. Such an illumination source is usually called a “strobo-light”.
In sports events, stroboscope techniques are of interest for analyzing the evolution over time and space of an athlete's gesture or stance, or other kinds of motion such as object trajectories, e.g. of balls, racquets, clubs and the like. Static photographic techniques are already in use, providing a “visual synopsis” of a fast sport action such as the 100 meter dash, for instance. Since, typically, the field of view of a static photographic camera cannot encompass the entire spatial extent of the athlete's course, relatively cumbersome solutions have been employed, in which several cameras are placed along the path of the athlete and synchronized so as to take a shot of the path when the athlete passes by. The resulting successive images can be joined together to compose a global view of the event in space and time.